Technical Abstract:
Enormous genomic resources have been developed for plants in the monocot order Poales; however it is not known how useful these resources will be for other economically important monocots. The Asparagales are a monophyletic order sister to the Class Commelinanae which carries the Poales, and is the second most economically important monocot order. Development of genomic resources for and their application to the Asparagales are challenging because of huge nuclear genomes and the relatively long generation times required to develop genetically defined families. We synthesized a normalized cDNA library of onion and produced 11,008 unique expressed sequence tags (ESTs) for comparative genomic analyses of the Asparagales and Poales. Alignments of onion ESTs, Poales ESTs, and genomic sequences from rice were used to design oligonucleotide primers amplifying genomic regions from asparagus, garlic, and onion. Sequence analyses of these genomic regions revealed microsatellite, indels, and single nucleotide polymorphisms for comparative mapping of rice and the Asparagales vegetables. Initial mapping revealed no obvious synteny at the recombinational level between onion and rice, indicating that genomic resources developed for the Poales may not be applicable to the monocots as a whole. Genomic analyses of the Asparagales would greatly benefit from EST sequencing and deep-coverage, large-insert genomic libraries of representative small-genome model species within the Higher and Lower Asparagales, such as asparagus and orchid respectively.